plat: xilinx: zynqmp: Initialize IPI table from zynqmp_config_setup()

Common ipi_table needs to be initialized before using any
IPI command (i.e send/receive). Move zynqmp ipi config table
initialization from sip_svc_setup() to zynqmp_config_setup().

Change-Id: Ic8aaa0728a43936cd4c6e1ed590e01ba8f0fbf5b
Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>